1. Field of the Invention
The present invention relates to a liquid crystal display device, and more particularly to a technique which is effectively applicable to a driver circuit of a liquid crystal display device used in a display part of a portable device.
2. Description of the Related Arts
A TFT (thin film transistor)-method liquid crystal display device has been popularly used as a display device of a personal computer, a television receiver set or the like. Such a liquid crystal display device includes a liquid crystal display panel and a driver circuit which drives the liquid crystal display panel.
With respect to such a liquid crystal display device, a miniaturized liquid crystal display device has been popularly used as a display device of portable equipment such as a mobile phone. In using the liquid crystal display device as the display device of the portable equipment, there has been a demand for a liquid crystal display device which can cope with complicated display modes compared to a conventional liquid crystal display device.
Japanese Patent Laid-open Hei08-211411 (Patent document 1) discloses a liquid crystal display device having counter electrodes belonging to two systems, wherein the liquid crystal display device adopts common voltages of opposite phases which invert polarities thereof from each other for every 1 frame. However, patent document 1 merely discloses the common voltages belonging to two systems and neither discloses nor suggests a control of outputting of the common voltages belonging to two systems.